A5100324355- Advanced Fiber Laser Technologies
- Advanced Frequency and Time Standards
- Quantum optics and atomic interactions
- Photonic and Optical Devices
- Spectroscopy and Laser Applications
- Semiconductor Lasers and Optical Devices
- Advanced Photonic Communication Systems
- Mechanical and Optical Resonators
- Atomic and Subatomic Physics Research
- Advanced Optical Sensing Technologies
- Quantum chaos and dynamical systems
- Quantum Information and Cryptography
- Particle accelerators and beam dynamics
- Advanced Technologies in Various Fields
- Optical Network Technologies
- Fusion materials and technologies
- Pulsed Power Technology Applications
- Ionosphere and magnetosphere dynamics
- Magnetic confinement fusion research
- Quantum and electron transport phenomena
- Quantum Mechanics and Non-Hermitian Physics
- Gyrotron and Vacuum Electronics Research
- Laser-Matter Interactions and Applications
- Non-Invasive Vital Sign Monitoring
Peking University
2013-2025
Chinese Academy of Sciences
2024
Beijing University of Posts and Telecommunications
2023
Beijing University of Chemical Technology
2017
Shanghai University
2008
Time and frequency transfer plays an important role in the fields of navigation positioning, remote sensing, fundamental physics. The performance long-haul is ultimately limited by accumulated phase amplitude noise fiber propagation. In this work we overcome these limitations demonstrate a system over 3000 km indoor spooled fibers via repetition-frequency-locked combs, which benefit from extremely high signal-to-noise ratio. With help digital discrimination compensation method active power...
The large-scale clock network is the key ingredient to obtain high precision in many scenarios, from fundamental research cutting-edge applications. advantage of time synchronization among microwave clocks their cost, size, and accessibility. Here, we demonstrate a femtosecond-level through commercial link 205.86 km via dual-comb-enhanced optical two-way transfer, which achieves 6.23-fs residual deviation between synchronized timescales at 1 s an instability below 6E-18 10,000 s. Further,...
Time transfer plays a dispensable role in many fields including navigation and positioning, geodesy, fundamental tests. However, certain scenarios where effective relay node deployment is often not feasible, such as harsh environments with extremely poor infrastructure emergency conditions, time without inline amplifiers becomes crucial. In this situation, the maximum transmission distance limited by receiver’s measurement capability, particularly its ability to amplify signal. Here, we...
Background Toxoplasma gondii (T. gondii) is an opportunistic intracellular parasite and a big threaten for patients with uremia solid organ transplantation recipients, especially kidney transplant recipients. However, seroprevalence in these patient populations remain unclear, the risk factors of post T. infection were not well-defined China globally. Methods Post-transplant or patient’s serum collected from center 3 rd Xiangya hospital Central South University detected by IHA to detect...
The Aharonov–Bohm effect in the background of a time-dependent vector potential is re-examined for both non-relativistic and relativistic cases. Based on solutions to Schrodinger Dirac equations which contain magnetic potential, we find that contrary conclusions recent paper (Singleton Vagenas 2013 [4]), interference pattern will be altered with respect time because potential.
High-precision time-interval measurement is a fundamental technique in many advanced applications, including time and distance metrology, particle physics, ultra-precision machining. However, of these applications are confined by the imprecise electrical signals, restricting performance ultimate system to few picoseconds, which limits ultra-high-precision applications. Here, we demonstrate an optical means signals that can successfully achieve femtosecond (fs)-level precision. The setup...
The large-scale clock network is the key ingredient to obtain high precision in many scenarios, from fundamental research cutting-edge applications. advantage of time synchronization among microwave clocks their cost, size, and accessibility. Here, we demonstrate a femtosecond-level through commercial link 205.86 km via dual-comb-enhanced optical two-way transfer, which achieves 6.23-fs residual deviation between synchronized timescales at 1 s an instability below 6×10 −18 10,000 s. Further,...
Optical frequency combs (OFCs), based on mode-locked lasers (MLLs), have attracted considerable attention in many fields over recent years. Among the applications of OFCs, one most challenging works is extraction a highly stable microwave with low phase noise. Many synchronisation schemes been exploited to synchronise an electronic oscillator pulse train from MLL, helping extract ultra-stable microwave. Here, we demonstrate novel wideband OFC by synchronising single widely tunable...
Optical clocks have been the focus of science and technology research areas due to their capability provide highest frequency accuracy stability date. Their superior performance promises significant advances in fields fundamental as well practical applications including satellite-based navigation ranging. In traditional optical clocks, ultrastable cavities, laser cooling particle (atoms or a single ion) trapping techniques are employed guarantee high accuracy. However, on other hand, they...
Fiber-delay measurement is one of the key fundamental technologies in numerous fields. Here, we propose and experimentally demonstrate a high-precision concise optical time delay system based on technique linear sampling, reaching precision better than 100 fs under averaging. The use only two frequency combs without locking carrier-envelope-offset greatly simplifies structure time-delay system. We also investigate current limitations timing jitter noises sources are mainly non-common mode...
We report the control of dressed state in three-mode optical entanglement an N-type four-level system using two cascaded parametric amplification four-wave mixing steps inside atom-like cavity and injected by thermal fields: a coherent field Einstein–Podolsky–Rosen field. First, dressing results Aulter–Towns-like (AT-like peak) anti-squeezing. And three-cavity interaction induces multi-AT-like peaks. Meanwhile, enhanced nonlinear gain one squeezing dip polariton. In addition, coupling three...
Abstract Scrape-off layer (SOL) profiles and turbulence in ion cyclotron range of frequency (ICRF)-heated plasmas are investigated by the reciprocating probe diagnostic system (FRPs) gas puff imaging (GPI) EAST. A radio-frequency (RF) sheath potential reaching up to 100 V is identified proximate ICRF antennas. Notably, amplitude this RF escalates response rising power inversely with plasma density. When a present far SOL, pronounced density ‘shoulder’ forms front antennas, while fade away as...
In the era of digital intelligence, rapid progress interdisciplinary fields and continuous expansion application domains have brought new challenges high standards to cultivation graduate talents in Management Science Engineering. Exploring effective innovative practical teaching approaches this field, strengthening comprehensive skills students has become a significant issue cultivating complex talents. Taking Guangdong University Finance & Economics as an example, study analyzes...
High-precision time transfer over a long haul of fiber plays significant role in many fields. The core method, namely cascading relay nodes for the compensation signal attenuation and dispersion, is however insufficient to deal with crucial point-to-point scenarios, such as harsh environments extremely deficient infrastructure emergency conditions. In long-distance transmission without any inline amplifiers, high loss optical link becomes primary limiting factor, direct use traditional...
SummaryIn this paper, the characteristics of EDFA have been measured under different experimental conditions based on optical comb frequency transfer, evaluated by NF and Gain curves. In case high input SNR, stability increases with increase gain, but in low conclusion is opposite. At same gain level, will be better SNR power. These conclusions can used to optimize parameters achieve higher our transfer system.
Possibility of bandwidth-limited slow light in superstructure fiber gratings is analyzed numerically, and the transmission spectra group delay are given. Intensity modulated Gauss pulse with FWHM 1.5 ns can be delayed about 1.2 grating modest distortion.
Mixer is of crucial importance in evaluating the precision frequency transfer. We present preliminary results on optimization practical mixer's LO and RF input power parameters when performing downconversion. A fractional instability better than 2E-13@1 s via 100 km fiber link with MHz repetition optical comb measured under optimized parameters.
We experimentally demonstrate a frequency transfer over 1000 km of fiber by exploiting the optical comb. Through feedback phase shifter, active noise cancellation is achieved. The fractional instability 2.4×10 <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">−15</sup> at 1 s and 1.1×10 xmlns:xlink="http://www.w3.org/1999/xlink">−18</sup> 10000 are measured respectively. results support ultrastable applications via long-haul links.
As an essential active device, electrical preamplifier has significant effect on frequency stability, which is extremely demanded by a transfer system. In this work, we build optical-comb based system and investigate the influences of noise in determining ultimate instability The experimental results show that increasing amplifier gain no contribution to improvement when higher than measuring 2E-14@1 s achieved with varying from 1 100. Moreover, if below 1E-15@1 be transferred, should...